fix typos

[vvyomjjain]

• closes #xxxx
• tests added / passed
• passes git diff upstream/master -u -- "*.py" | flake8 --diff
• whatsnew entry

[jreback]

thanks!

[codecov]

Codecov Report

Merging #23003 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #23003   +/-   ##
=======================================
  Coverage   92.19%   92.19%           
=======================================
  Files         169      169           
  Lines       50831    50831           
=======================================
  Hits        46864    46864           
  Misses       3967     3967

Flag	Coverage Δ
#multiple	90.61% <ø> (ø)	⬆️
#single	42.35% <ø> (ø)	⬆️

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